Package configurations for low EMI circuits

Abstract

An electronic component includes a high voltage switching transistor encased in a package. The high voltage switching transistor comprises a source electrode, a gate electrode, and a drain electrode all on a first side of the high voltage switching transistor. The source electrode is electrically connected to a conducting structural portion of the package. Assemblies using the abovementioned transistor with another transistor can be formed, where the source of one transistor can be electrically connected to a conducting structural portion of a package containing the transistor and a drain of the second transistor is electrically connected to the second conductive structural portion of a package that houses the second transistor. Alternatively, the source of the second transistor is electrically isolated from its conductive structural portion, and the drain of the second transistor is electrically isolated from its conductive structural portion.

What is claimed is: 
     
       1. An assembly, comprising:
 a first transistor comprising a first source, the first transistor encased in a first package, the first package comprising a first conductive structural portion, and 
 a second transistor comprising a second source and a second drain, the second transistor encased in a second package, the second package comprising a second conductive structural portion, wherein 
 the first source is electrically connected to the first conductive structural portion, the second source is electrically isolated from the second conductive structural portion, and the second drain is electrically isolated from the second conductive structural portion. 
 
     
     
       2. The assembly of  claim 1 , wherein the first transistor or the second transistor is a high voltage switching transistor. 
     
     
       3. The assembly of  claim 1 , wherein the first conductive structural portion or the second conductive structural portion is mounted directly on a heat sink and is electrically connected to the heat sink. 
     
     
       4. The assembly of  claim 1 , wherein the first conductive structural portion or the second conductive structural portion is electrically connected to a circuit ground. 
     
     
       5. The assembly of  claim 1 , wherein the first drain is electrically connected to the second source. 
     
     
       6. The assembly of  claim 5 , wherein the first transistor is a low-side switch and the second transistor is a high-side switch. 
     
     
       7. A half bridge comprising the assembly of  claim 1 . 
     
     
       8. The assembly of  claim 1 , wherein the first transistor or the second transistor is a III-N transistor. 
     
     
       9. The assembly of  claim 1 , wherein the first transistor or the second transistor is a lateral device. 
     
     
       10. An assembly, comprising:
 a first transistor comprising a first source and a first drain, the first transistor encased in a first package; and 
 a second transistor comprising a second source and a second drain, the second transistor encased in a second package; wherein 
 the first package comprises a first conductive structural portion and a first drain lead; 
 the second package comprises a second conductive structural portion and a second source lead; 
 the first source is electrically connected to the first conductive structural portion; 
 the second source is electrically isolated from the second conductive structural portion; and 
 the first drain lead is electrically connected to the second source lead. 
 
     
     
       11. The assembly of  claim 10 , wherein the first conductive structural portion or the second conductive structural portion is electrically connected to a circuit ground. 
     
     
       12. The assembly of  claim 10 , wherein the first transistor or the second transistor is a lateral device. 
     
     
       13. The assembly of  claim 10 , wherein the first transistor or the second transistor is a III-N transistor. 
     
     
       14. The assembly of  claim 10 , the first package further comprising a first source lead and a first gate lead, wherein the first source lead is between the first gate lead and the first drain lead. 
     
     
       15. The assembly of  claim 14 , the first package further comprising a case, the case comprising the first conductive structural portion and a first insulating portion, wherein the gate lead, the source lead, and the drain lead each extend from the first insulating portion. 
     
     
       16. An assembly, comprising:
 a first transistor comprising a semiconductor layer, a first source, and a first drain, the first transistor encased in a first package; and 
 a second transistor comprising a second source and a second drain, the second transistor encased in a second package; wherein 
 the first package comprises a first conductive structural portion, a first source lead, a first gate lead, and a first drain lead, the first source lead being between the first gate lead and the first drain lead; 
 the first source and the first drain are each on an opposite side of the semiconductor layer from the first conductive structural portion; 
 the second package comprises a second conductive structural portion; and the second source is electrically isolated from the second conductive structural portion. 
 
     
     
       17. The assembly of  claim 16 , wherein the first source is electrically connected to the first conductive structural portion. 
     
     
       18. The assembly of  claim 16 , the second package further comprising a second source lead, wherein the first drain lead is electrically connected to the second source lead. 
     
     
       19. The assembly of  claim 16 , wherein the first transistor or the second transistor is a III-N transistor. 
     
     
       20. The assembly of  claim 16 , wherein the second drain is electrically isolated from the second conductive structural portion. 
     
     
       21. An assembly, comprising:
 a first transistor comprising a first source, the first transistor encased in a first package, the first package comprising a first conductive structural portion; and 
 a second transistor comprising a second source and encased in a second package, the second package comprising a second conductive structural portion and three leads; wherein 
 the first source is electrically connected to the first conductive structural portion, the second source is electrically isolated from the second conductive structural portion, and the three leads are each electrically isolated from the second conductive structural portion. 
 
     
     
       22. The assembly of  claim 21 , wherein the first transistor or the second transistor is a lateral device. 
     
     
       23. The assembly of  claim 21 , wherein the first transistor or the second transistor is a III-N transistor.